メタアナリシスと,その後の大規模対照試験の間の不一致を解決する
1Division of Epidemiology, Statistics, and Prevention Research, National Institute of Child Health and Development, Bethesda, MD 20892-7510, USA. DerSimonian@nih.gov
JAMA
|October 12, 1999
まとめ
カルシウム補給は,高リスクの健康な女性では妊娠前出血症を予防する可能性があるが,低リスクの女性ではそうではない. 高リスクグループにおける有効性を確認するためにさらなる研究が必要である. 妊産前出血栓症の予防は,依然として研究対象分野である.
科学分野:
- 産婦人科と産婦人科を担当しています.
- 栄養科学とは,栄養科学である.
- 臨床流行病学 臨床流行病学とは
背景:
- メタアナリシスによると,カルシウムサプリメントは妊娠前出血症を効果的に防ぐことが示されています.
- NIH Calcium for Preeclampsia Prevention (CPEP) 試験では,健康なヌリポラスの女性ではリスクが低下していないことが判明しました.
- 研究間の不一致は,出産前不妊症の予防におけるカルシウムの役割に関するさらなる調査を必要とします.
研究 の 目的:
- メタアナリシスとCPEP試験の矛盾する結果を調和させるため.
- 効果の異質性の研究不一致に対する影響を評価する.
- 妊娠前出血症の予防のためのカルシウム補給の有効性を評価する.
主な方法:
- 1997年7月10日以前に出版された英語記事の体系的な文献レビュー.
- 妊娠前出血症とカルシウムサプリメントに関するデータを報告した試験を含む.
- 14件の試験の分析,プラセボ対照群とリスク集団 (高リスク対低リスク) による層分化.
主要な成果:
- 試験全体で実質的な異質性が見られた (P = .001).
- 低リスク集団を対象としたプラセボ対照試験では,カルシウムは有意な効果を示さなかった (RR,0.79;P = .30),CPEP試験の結果と一致した.
- 健康な高リスク集団では,カルシウムは強い利点を示唆した (RR,0.19;P = .001),しかし,サンプルサイズが小さくて (n=225) データが一貫していないため,結果は曖昧であった.
結論:
- 健康な高リスク集団における妊娠前出血症の予防のためのカルシウム補給の有効性は,さらなる調査を必要としています.
- 単一の要約指標は,有意な異質性を持つメタ分析では不十分です.
- 異質性を減らすための共変数を特定することは,治療戦略の最適化に不可欠です.
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